Road Test: Audio-Technica System 10 Digital Wireless System

Evaluating a new system operating in the 2.4 GHz band

Audio-Technica’s first entry into digital wireless was SpectraPulse, a specialized system for secure conferencing applications. Now with the new System 10, A-T has brought digital wireless into a simple format at popular price points.

System 10 is not a professional touring wireless microphone system, like the company’s 4000 and 5000 Series, yet it implements some impressive technology in an easy-to-use package. The system sounds good and contains a variety of integral features that solve common wireless performance and coordination problems.

Operating in the 2.4 GHz band, System 10 allows up to eight units to work together, depending on interference conditions from wi-fi and other devices in that band. The system is designed to automatically search out clear frequencies, work fluidly with multiple channels of wireless in the same location, and maintain bi-directional communication between paired transmitters and receivers.

Multiple Diversity Methods
The transmission scheme uses three different diversity methods, which all happen “behind the scenes” – a mix of frequency, time, and space diversity.

Beginning with frequency diversity, the handheld and beltpack transmit on two different frequencies simultaneously, and the receiver selects the one with the highest signal-to-noise ratio to convert to audio. When the receiver is turned on, it selects these frequencies after surveying the RF environment, and communicates them to the associated transmitter as soon as it is on.

System 10 half-rack-sized ATW-R100 receiver, made for stand-alone use. (click to enlarge)

The receiver also selects a couple additional clear frequencies for backup at turn-on. If one of the active frequencies is encountering significant interference during use, the receiver automatically selects and relays a clear frequency to the transmitter, replacing the one experiencing interference.

In addition, the digital audio “data packets” are transmitted in slightly different time slots. Thus the identical data is received twice, and the packet without errors is decoded within the receiver, countering potential multipath problems. System 10 also uses space diversity with a twist, adding a pair of spaced antennas in the transmitter each sending a signal, along with the standard dual antennas on the receiver.

System Pairing
A-T uses a process of “pairing” a transmitter with a receiver, so that they communicate bi-directionally and function as a unit. After selecting a channel ID number 1 through 8, the user presses the pairing button on the receiver and subsequently activates the button in the transmitter’s battery compartment at close range to sync them together. The transmitter’s display now shows the same ID number, and the system is ready to use.

ATW-T1002 handheld transmitter with LED on the body clearly showing channel. (click to enlarge)

The system number shown in the display is solely for identification of the paired systems, and has no relationship to the frequencies the unit is transmitting on. In fact, all of the systems being used together could have the same displayed ID number and would still function as a coordinated installation. At various times when the same unit is used, it may well be using a different set of frequencies based on what is currently clear and available.

The pairing method is quick to learn, and can be used to switch between a handheld and bodypack using the same receiver, or to add a new transmitter to the system. I attempted to pair a transmitter with two receivers to see if redundancy is possible, but only a one-to-one relationship is permitted.

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Audio Quality
System 10 is fully digital, offering 24-bit/48-kHz audio with no analog companding circuitry or the potential interference effects possible with analog transmission that result from interference or low signal strength.

The handheld mic sounds good, featuring balanced lows without excessive proximity effect, as well as even mids and sufficient highs for intelligibility – though not as crisp and articulate as a higher end condenser would yield. The polar pattern appears to fall somewhere between supercardioid and cardioid, with the deepest nulls around 75 to 80 degrees off-axis.